Dr. Zhongsheng Guo studied soil sciences at Northwestern A & F University, China, and graduated with an MS in 2000. He then researches the high-quality and sustainable method of forest, grass, crop and soil and water conservation in Northwestern A & F University, CAS & MWR. He received him PhD degree in 2004 at the Northwestern A & F University. He obtained the position of an Professor at Northwestern A & F University,CAS & MWR. He has published a couple of research articles in SCI(E) journals. He put forward the resource use limit by plants (RULP), vegetation carrying capacity (VCC) , the critical period of plant resource relationship regulation, and the new theory of soil and water conservation.